Getting a 318 running?

By the looks of the cam and sludge on the rocker arms, I would say you have a stock 100K + motor.
New soft plugs and water pump would lead me to believe there was an over-heating issue, or rust in the coolent system.
Pull all the plugs, if they look like the one you showed it is just gas fouled, clean or replace all of them.

Since it is on the stand I would drop the oil pan, and timing chain cover and look everything over real good.
At best it may need a new tiiming chain, if the timing chain is shot look for broken plastic teeth, if this is case, pull the oil pump off, the oil pick up catch the broken teeth, and may sound like a baby rattle.
Throw a new gasket set it, there was a reason the engine was greasy to begin with.